首先，问题中的代码不会产生所描述的输出。它提取文件扩展名(“txt”)，而不是文件基名(“hello”)。要做到这一点，最后一行应该调用First()，而不是last()，就像这样…

static string GetFileBaseNameUsingSplit(string path)
{
    string[] pathArr = path.Split('\\');
    string[] fileArr = pathArr.Last().Split('.');
    string fileBaseName = fileArr.First().ToString();

    return fileBaseName;
}

在做了这样的更改之后，要考虑的一件事是改进这段代码所产生的垃圾数量:

一个字符串[]，为path中的每个路径段包含一个字符串 一个字符串[]，每个字符串至少包含一个字符串。在path的最后一个路径段中

因此，从示例路径“C:\Program Files\hello.txt”中提取基文件名应该会产生(临时)对象“C:”，“Program Files”，“hello.txt”，“hello”，“txt”，一个字符串[3]和一个字符串[2]。如果在大量路径上调用该方法，这可能很重要。为了改进这一点，我们可以自己搜索路径来定位基本名称的起始点和结束点，并使用它们来创建一个新的字符串…

static string GetFileBaseNameUsingSubstringUnsafe(string path)
{
    // Fails on paths with no file extension - DO NOT USE!!
    int startIndex = path.LastIndexOf('\\') + 1;
    int endIndex = path.IndexOf('.', startIndex);
    string fileBaseName = path.Substring(startIndex, endIndex - startIndex);

    return fileBaseName;
}

这是使用最后一个\之后的字符的索引作为基本名称的开始，并从那里寻找第一个字符。用作基名末尾字符的索引。这比原来的代码短吗?不完全是。这是一个“更聪明”的解决方案吗?我想是的。至少，如果不是因为……

从评论中可以看出，前面的方法是有问题的。虽然如果假设所有路径都以带扩展名的文件名结束，那么它会工作，但如果路径以\结束(即目录路径)或在最后一段中不包含扩展名，它将抛出异常。为了解决这个问题，我们需要添加一个额外的检查，以考虑当endIndex为-1(即。未找到)…

static string GetFileBaseNameUsingSubstring(string path)
{
    int startIndex = path.LastIndexOf('\\') + 1;
    int endIndex = path.IndexOf('.', startIndex);
    int length = (endIndex >= 0 ? endIndex : path.Length) - startIndex;
    string fileBaseName = path.Substring(startIndex, length);

    return fileBaseName;
}

现在这个版本比原来的更短，但它更有效，(现在)也更正确。

As far as .NET methods that implement this functionality, many other answers suggest using Path.GetFileNameWithoutExtension(), which is an obvious, easy solution but does not produce the same results as the code in the question. There is a subtle but important difference between GetFileBaseNameUsingSplit() and Path.GetFileNameWithoutExtension() (GetFileBaseNameUsingPath() below): the former extracts everything before the first . and the latter extracts everything before the last .. This doesn't make a difference for the sample path in the question, but take a look at this table comparing the results of the above four methods when called with various paths...

.．.并且你会看到path . getfilenamewithoutextension()在传递文件名有双扩展名或前导和/或尾随的路径时产生不同的结果。你可以用下面的代码自己试试…

using System;
using System.IO;
using System.Linq;
using System.Reflection;

namespace SO6921105
{
    internal class PathExtractionResult
    {
        public string Description { get; set; }
        public string Method { get; set; }
        public string Path { get; set; }
        public string Result { get; set; }
    }

    public static class Program
    {
        private static string GetFileBaseNameUsingSplit(string path)
        {
            string[] pathArr = path.Split('\\');
            string[] fileArr = pathArr.Last().Split('.');
            string fileBaseName = fileArr.First().ToString();

            return fileBaseName;
        }

        private static string GetFileBaseNameUsingPath(string path)
        {
            return Path.GetFileNameWithoutExtension(path);
        }

        private static string GetFileBaseNameUsingSubstringUnsafe(string path)
        {
            // Fails on paths with no file extension - DO NOT USE!!
            int startIndex = path.LastIndexOf('\\') + 1;
            int endIndex = path.IndexOf('.', startIndex);
            string fileBaseName = path.Substring(startIndex, endIndex - startIndex);

            return fileBaseName;
        }

        private static string GetFileBaseNameUsingSubstring(string path)
        {
            int startIndex = path.LastIndexOf('\\') + 1;
            int endIndex = path.IndexOf('.', startIndex);
            int length = (endIndex >= 0 ? endIndex : path.Length) - startIndex;
            string fileBaseName = path.Substring(startIndex, length);

            return fileBaseName;
        }

        public static void Main()
        {
            MethodInfo[] testMethods = typeof(Program).GetMethods(BindingFlags.NonPublic | BindingFlags.Static)
                .Where(method => method.Name.StartsWith("GetFileBaseName"))
                .ToArray();
            var inputs = new[] {
                new { Description = "Single extension",      Path = @"C:\Program Files\hello.txt"     },
                new { Description = "Double extension",      Path = @"C:\Program Files\hello.txt.ext" },
                new { Description = "No extension",          Path = @"C:\Program Files\hello"         },
                new { Description = "Leading period",        Path = @"C:\Program Files\.hello.txt"    },
                new { Description = "Trailing period",       Path = @"C:\Program Files\hello.txt."    },
                new { Description = "Directory path",        Path = @"C:\Program Files\"              },
                new { Description = "Current file path",     Path = "hello.txt"                       },
                new { Description = "Parent file path",      Path = @"..\hello.txt"                   },
                new { Description = "Parent directory path", Path = ".."                              }
            };
            PathExtractionResult[] results = inputs
                .SelectMany(
                    input => testMethods.Select(
                        method => {
                            string result;

                            try
                            {
                                string returnValue = (string) method.Invoke(null, new object[] { input.Path });

                                result = $"\"{returnValue}\"";
                            }
                            catch (Exception ex)
                            {
                                if (ex is TargetInvocationException)
                                    ex = ex.InnerException;
                                result = $"EXCEPTION: {ex.Message}";
                            }

                            return new PathExtractionResult() {
                                Description = input.Description,
                                Method = $"{method.Name}()",
                                Path = $"\"{input.Path}\"",
                                Result = result
                            };
                        }
                    )
                ).ToArray();
            const int ColumnPadding = 2;
            ResultWriter writer = new ResultWriter(Console.Out) {
                DescriptionColumnWidth = results.Max(output => output.Description.Length) + ColumnPadding,
                MethodColumnWidth = results.Max(output => output.Method.Length) + ColumnPadding,
                PathColumnWidth = results.Max(output => output.Path.Length) + ColumnPadding,
                ResultColumnWidth = results.Max(output => output.Result.Length) + ColumnPadding,
                ItemLeftPadding = " ",
                ItemRightPadding = " "
            };
            PathExtractionResult header = new PathExtractionResult() {
                Description = nameof(PathExtractionResult.Description),
                Method = nameof(PathExtractionResult.Method),
                Path = nameof(PathExtractionResult.Path),
                Result = nameof(PathExtractionResult.Result)
            };

            writer.WriteResult(header);
            writer.WriteDivider();
            foreach (IGrouping<string, PathExtractionResult> resultGroup in results.GroupBy(result => result.Description))
            {
                foreach (PathExtractionResult result in resultGroup)
                    writer.WriteResult(result);
                writer.WriteDivider();
            }
        }
    }

    internal class ResultWriter
    {
        private const char DividerChar = '-';
        private const char SeparatorChar = '|';

        private TextWriter Writer { get; }

        public ResultWriter(TextWriter writer)
        {
            Writer = writer ?? throw new ArgumentNullException(nameof(writer));
        }

        public int DescriptionColumnWidth { get; set; }

        public int MethodColumnWidth { get; set; }

        public int PathColumnWidth { get; set; }

        public int ResultColumnWidth { get; set; }

        public string ItemLeftPadding { get; set; }

        public string ItemRightPadding { get; set; }

        public void WriteResult(PathExtractionResult result)
        {
            WriteLine(
                $"{ItemLeftPadding}{result.Description}{ItemRightPadding}",
                $"{ItemLeftPadding}{result.Method}{ItemRightPadding}",
                $"{ItemLeftPadding}{result.Path}{ItemRightPadding}",
                $"{ItemLeftPadding}{result.Result}{ItemRightPadding}"
            );
        }

        public void WriteDivider()
        {
            WriteLine(
                new string(DividerChar, DescriptionColumnWidth),
                new string(DividerChar, MethodColumnWidth),
                new string(DividerChar, PathColumnWidth),
                new string(DividerChar, ResultColumnWidth)
            );
        }

        private void WriteLine(string description, string method, string path, string result)
        {
            Writer.Write(SeparatorChar);
            Writer.Write(description.PadRight(DescriptionColumnWidth));
            Writer.Write(SeparatorChar);
            Writer.Write(method.PadRight(MethodColumnWidth));
            Writer.Write(SeparatorChar);
            Writer.Write(path.PadRight(PathColumnWidth));
            Writer.Write(SeparatorChar);
            Writer.Write(result.PadRight(ResultColumnWidth));
            Writer.WriteLine(SeparatorChar);
        }
    }
}

问题中的代码在某些极端情况下的行为并不像许多人所期望的那样。如果您打算编写自己的路径操作代码，请务必考虑到…

.．.如何定义“没有扩展名的文件名”(它是在第一个之前的所有内容吗?)还是之前的一切?) .．.具有多个扩展名的文件 .．.没有扩展名的文件 .．.带前导的文件。 .．.带拖尾的文件。(可能你在Windows上不会遇到这种情况，但它们是有可能的) .．.具有“扩展名”或以其他方式包含。 .．.以\结尾的路径 .．.相对路径

并非所有文件路径都遵循X:\Directory\ file .ext!

string Location = "C:\\Program Files\\hello.txt";

string FileName = Location.Substring(Location.LastIndexOf('\\') +
    1);

Namespace: using System.IO;  
 //use this to get file name dynamically 
 string filelocation = Properties.Settings.Default.Filelocation;
//use this to get file name statically 
//string filelocation = @"D:\FileDirectory\";
string[] filesname = Directory.GetFiles(filelocation); //for multiple files
    

你在App.config文件中的路径配置如果你要动态获取文件名

    <userSettings>
        <ConsoleApplication13.Properties.Settings>
          <setting name="Filelocation" serializeAs="String">
            <value>D:\\DeleteFileTest</value>
          </setting>
              </ConsoleApplication13.Properties.Settings>
      </userSettings>

首先，问题中的代码不会产生所描述的输出。它提取文件扩展名(“txt”)，而不是文件基名(“hello”)。要做到这一点，最后一行应该调用First()，而不是last()，就像这样…

static string GetFileBaseNameUsingSplit(string path)
{
    string[] pathArr = path.Split('\\');
    string[] fileArr = pathArr.Last().Split('.');
    string fileBaseName = fileArr.First().ToString();

    return fileBaseName;
}

在做了这样的更改之后，要考虑的一件事是改进这段代码所产生的垃圾数量:

一个字符串[]，为path中的每个路径段包含一个字符串 一个字符串[]，每个字符串至少包含一个字符串。在path的最后一个路径段中

因此，从示例路径“C:\Program Files\hello.txt”中提取基文件名应该会产生(临时)对象“C:”，“Program Files”，“hello.txt”，“hello”，“txt”，一个字符串[3]和一个字符串[2]。如果在大量路径上调用该方法，这可能很重要。为了改进这一点，我们可以自己搜索路径来定位基本名称的起始点和结束点，并使用它们来创建一个新的字符串…

static string GetFileBaseNameUsingSubstringUnsafe(string path)
{
    // Fails on paths with no file extension - DO NOT USE!!
    int startIndex = path.LastIndexOf('\\') + 1;
    int endIndex = path.IndexOf('.', startIndex);
    string fileBaseName = path.Substring(startIndex, endIndex - startIndex);

    return fileBaseName;
}

这是使用最后一个\之后的字符的索引作为基本名称的开始，并从那里寻找第一个字符。用作基名末尾字符的索引。这比原来的代码短吗?不完全是。这是一个“更聪明”的解决方案吗?我想是的。至少，如果不是因为……

从评论中可以看出，前面的方法是有问题的。虽然如果假设所有路径都以带扩展名的文件名结束，那么它会工作，但如果路径以\结束(即目录路径)或在最后一段中不包含扩展名，它将抛出异常。为了解决这个问题，我们需要添加一个额外的检查，以考虑当endIndex为-1(即。未找到)…

static string GetFileBaseNameUsingSubstring(string path)
{
    int startIndex = path.LastIndexOf('\\') + 1;
    int endIndex = path.IndexOf('.', startIndex);
    int length = (endIndex >= 0 ? endIndex : path.Length) - startIndex;
    string fileBaseName = path.Substring(startIndex, length);

    return fileBaseName;
}

现在这个版本比原来的更短，但它更有效，(现在)也更正确。

As far as .NET methods that implement this functionality, many other answers suggest using Path.GetFileNameWithoutExtension(), which is an obvious, easy solution but does not produce the same results as the code in the question. There is a subtle but important difference between GetFileBaseNameUsingSplit() and Path.GetFileNameWithoutExtension() (GetFileBaseNameUsingPath() below): the former extracts everything before the first . and the latter extracts everything before the last .. This doesn't make a difference for the sample path in the question, but take a look at this table comparing the results of the above four methods when called with various paths...

.．.并且你会看到path . getfilenamewithoutextension()在传递文件名有双扩展名或前导和/或尾随的路径时产生不同的结果。你可以用下面的代码自己试试…

using System;
using System.IO;
using System.Linq;
using System.Reflection;

namespace SO6921105
{
    internal class PathExtractionResult
    {
        public string Description { get; set; }
        public string Method { get; set; }
        public string Path { get; set; }
        public string Result { get; set; }
    }

    public static class Program
    {
        private static string GetFileBaseNameUsingSplit(string path)
        {
            string[] pathArr = path.Split('\\');
            string[] fileArr = pathArr.Last().Split('.');
            string fileBaseName = fileArr.First().ToString();

            return fileBaseName;
        }

        private static string GetFileBaseNameUsingPath(string path)
        {
            return Path.GetFileNameWithoutExtension(path);
        }

        private static string GetFileBaseNameUsingSubstringUnsafe(string path)
        {
            // Fails on paths with no file extension - DO NOT USE!!
            int startIndex = path.LastIndexOf('\\') + 1;
            int endIndex = path.IndexOf('.', startIndex);
            string fileBaseName = path.Substring(startIndex, endIndex - startIndex);

            return fileBaseName;
        }

        private static string GetFileBaseNameUsingSubstring(string path)
        {
            int startIndex = path.LastIndexOf('\\') + 1;
            int endIndex = path.IndexOf('.', startIndex);
            int length = (endIndex >= 0 ? endIndex : path.Length) - startIndex;
            string fileBaseName = path.Substring(startIndex, length);

            return fileBaseName;
        }

        public static void Main()
        {
            MethodInfo[] testMethods = typeof(Program).GetMethods(BindingFlags.NonPublic | BindingFlags.Static)
                .Where(method => method.Name.StartsWith("GetFileBaseName"))
                .ToArray();
            var inputs = new[] {
                new { Description = "Single extension",      Path = @"C:\Program Files\hello.txt"     },
                new { Description = "Double extension",      Path = @"C:\Program Files\hello.txt.ext" },
                new { Description = "No extension",          Path = @"C:\Program Files\hello"         },
                new { Description = "Leading period",        Path = @"C:\Program Files\.hello.txt"    },
                new { Description = "Trailing period",       Path = @"C:\Program Files\hello.txt."    },
                new { Description = "Directory path",        Path = @"C:\Program Files\"              },
                new { Description = "Current file path",     Path = "hello.txt"                       },
                new { Description = "Parent file path",      Path = @"..\hello.txt"                   },
                new { Description = "Parent directory path", Path = ".."                              }
            };
            PathExtractionResult[] results = inputs
                .SelectMany(
                    input => testMethods.Select(
                        method => {
                            string result;

                            try
                            {
                                string returnValue = (string) method.Invoke(null, new object[] { input.Path });

                                result = $"\"{returnValue}\"";
                            }
                            catch (Exception ex)
                            {
                                if (ex is TargetInvocationException)
                                    ex = ex.InnerException;
                                result = $"EXCEPTION: {ex.Message}";
                            }

                            return new PathExtractionResult() {
                                Description = input.Description,
                                Method = $"{method.Name}()",
                                Path = $"\"{input.Path}\"",
                                Result = result
                            };
                        }
                    )
                ).ToArray();
            const int ColumnPadding = 2;
            ResultWriter writer = new ResultWriter(Console.Out) {
                DescriptionColumnWidth = results.Max(output => output.Description.Length) + ColumnPadding,
                MethodColumnWidth = results.Max(output => output.Method.Length) + ColumnPadding,
                PathColumnWidth = results.Max(output => output.Path.Length) + ColumnPadding,
                ResultColumnWidth = results.Max(output => output.Result.Length) + ColumnPadding,
                ItemLeftPadding = " ",
                ItemRightPadding = " "
            };
            PathExtractionResult header = new PathExtractionResult() {
                Description = nameof(PathExtractionResult.Description),
                Method = nameof(PathExtractionResult.Method),
                Path = nameof(PathExtractionResult.Path),
                Result = nameof(PathExtractionResult.Result)
            };

            writer.WriteResult(header);
            writer.WriteDivider();
            foreach (IGrouping<string, PathExtractionResult> resultGroup in results.GroupBy(result => result.Description))
            {
                foreach (PathExtractionResult result in resultGroup)
                    writer.WriteResult(result);
                writer.WriteDivider();
            }
        }
    }

    internal class ResultWriter
    {
        private const char DividerChar = '-';
        private const char SeparatorChar = '|';

        private TextWriter Writer { get; }

        public ResultWriter(TextWriter writer)
        {
            Writer = writer ?? throw new ArgumentNullException(nameof(writer));
        }

        public int DescriptionColumnWidth { get; set; }

        public int MethodColumnWidth { get; set; }

        public int PathColumnWidth { get; set; }

        public int ResultColumnWidth { get; set; }

        public string ItemLeftPadding { get; set; }

        public string ItemRightPadding { get; set; }

        public void WriteResult(PathExtractionResult result)
        {
            WriteLine(
                $"{ItemLeftPadding}{result.Description}{ItemRightPadding}",
                $"{ItemLeftPadding}{result.Method}{ItemRightPadding}",
                $"{ItemLeftPadding}{result.Path}{ItemRightPadding}",
                $"{ItemLeftPadding}{result.Result}{ItemRightPadding}"
            );
        }

        public void WriteDivider()
        {
            WriteLine(
                new string(DividerChar, DescriptionColumnWidth),
                new string(DividerChar, MethodColumnWidth),
                new string(DividerChar, PathColumnWidth),
                new string(DividerChar, ResultColumnWidth)
            );
        }

        private void WriteLine(string description, string method, string path, string result)
        {
            Writer.Write(SeparatorChar);
            Writer.Write(description.PadRight(DescriptionColumnWidth));
            Writer.Write(SeparatorChar);
            Writer.Write(method.PadRight(MethodColumnWidth));
            Writer.Write(SeparatorChar);
            Writer.Write(path.PadRight(PathColumnWidth));
            Writer.Write(SeparatorChar);
            Writer.Write(result.PadRight(ResultColumnWidth));
            Writer.WriteLine(SeparatorChar);
        }
    }
}

问题中的代码在某些极端情况下的行为并不像许多人所期望的那样。如果您打算编写自己的路径操作代码，请务必考虑到…

.．.如何定义“没有扩展名的文件名”(它是在第一个之前的所有内容吗?)还是之前的一切?) .．.具有多个扩展名的文件 .．.没有扩展名的文件 .．.带前导的文件。 .．.带拖尾的文件。(可能你在Windows上不会遇到这种情况，但它们是有可能的) .．.具有“扩展名”或以其他方式包含。 .．.以\结尾的路径 .．.相对路径

并非所有文件路径都遵循X:\Directory\ file .ext!

你可以像下面这样使用Path API:

 var filenNme = Path.GetFileNameWithoutExtension([File Path]);

更多信息:路径。GetFileNameWithoutExtension

试试这个:

string fileName = Path.GetFileNameWithoutExtension(@"C:\Program Files\hello.txt");

这将为fileName返回“hello”。